powerpc/process: Fix altivec SPR not being saved
In save_sprs() in process.c contains the following test: if (cpu_has_feature(cpu_has_feature(CPU_FTR_ALTIVEC))) t->vrsave = mfspr(SPRN_VRSAVE); CPU feature with the mask 0x1 is CPU_FTR_COHERENT_ICACHE so the test is equivilent to: if (cpu_has_feature(CPU_FTR_ALTIVEC) && cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) On CPUs without support for both (i.e G5) this results in vrsave not being saved between context switches. The vector register save/restore code doesn't use VRSAVE to determine which registers to save/restore, but the value of VRSAVE is used to determine if altivec is being used in several code paths. Fixes: 152d523e ("powerpc: Create context switch helpers save_sprs() and restore_sprs()") Cc: stable@vger.kernel.org Signed-off-by:Oliver O'Halloran <oohall@gmail.com> Signed-off-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au>
parent
08a5bb29
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